> ...I prefer to think in terms of the two theories of evolution:
> The Special Theory of Evolution and The General Theory
> of Evolution.
>
> The Special Theory of Evolution is expressed by two
> propositions:
>
> 1. Changes occur to the genomes of species.
>
> 2. These changes are caused and preserved by natural
> mechanisms.
>
> The proof of the Special Theory is in the fact that such
> changes have been observed to occur in nature and that
> their causes can be accounted for. Moreover, "micro"
> changes can theoretically--some say certainly--accumulate
> into "macro" changes--even to the formation of new
> species.
>
> The General Theory of Evolution is also expressed by two
> propositions:
>
> 1. Natural mechanisms account for all changes to the
> genomes of all species.
>
> 2. All biodiversity on earth is attributable to these natural
> mechanisms.
>
> The proof of the General Theory would be established by
> thorough models of physiological and biochemical evolution
> derived from a complete fossil record and extensive analysis
> of the preserved DNA of ancient species. Moreover, all
> extra-natural activity must be completely and impartially
> discounted.
Stephen Jones replied:
> I can't see a clear distinction between the Special and
> General Theory of Evolution. What is the difference between:
>
> "1. Changes occur to the genomes of species."
>
> and
>
> "1. Natural mechanisms account for all changes to the
> genomes of all species."
>
> Or between:
>
> "2. These changes are caused and preserved by natural
> mechanisms."
>
> and
>
> "2. All biodiversity on earth is attributable to these natural
> mechanisms."
The difference is the word "all". The Special Theory says that certain things
happened. The General Theory does exactly what its name implies; it generalizes
"some" observations onto "all" potential circumstances through "all" time.
Saying natural events occur--the Special Theory--is not the same as saying they
account for "all" possible events that could have occurred--the General Theory.
Steve quoted from Denton:
> Denton makes a good distinction between Darwin's
> Special and General theories:
>
> "In his book Darwin is actually presenting two related but
> quite distinct theories. The first, which has sometimes been
> called the "special theory", is relatively conservative and
> restricted in scope and merely proposes that new races
> and species arise in nature by the agency of natural
> selection...The second theory, which is often called the
> "general theory", is far more radical. It makes the claim that
> the "special theory" applies universally and hence that the
> appearance of all the manifold diversity of life on Earth can
> be explained by a simple extrapolation of the processes
> which bring about relatively trivial changes such as those
> seen on the Galapagos Islands. This "general theory" is
> what most people think of when they refer to evolution
> theory.' (Denton M., "Evolution: A Theory in Crisis", 1985,
> p44)
Notice the terms "applies universally" and "all...diversity" . I basically
said--or at least meant to say--the same thing. He throws in the point at the
end that is worth emphasizing, however, that when the average person thinks of
evolution, it is the General Theory that he has in mind. The difference between
the Special and General Theories of Evolution are wholly beyond the knowledge or
interest of the average person. It is enough for him to "know" that scientists
have proved evolution to be true because they've discovered the minor changes
occurring in nature. Little does he realize that the generalization of these
changes into the entire biosphere is no more proven now than in Darwin's day.
The part remains a theory is the very part that most people believe is solidly
proved.
Russ